This .Net error typically occurs when the underlying collection is modified during enumeration. For example if you remove items from the collection while enumerating the collection. It can also happen when you're accessing a collection while adding to the collection. See if you can see the bug in the...
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If you need to create a composite key (for a dictionary for example) where the natural key could come from multiple sources a standard technique is to prepend the source to the natural key to ensure that it is unique. However, this can still cause duplicate keys so to solve this problem you should always...
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The CSS files in a web application don't change very often. For this reason they are usually cached by the browser to improve performance. These are the steps that I take to optimize CSS files from my web apps. Although I'm using ASP.NET MVC this can be applied to any web app written in any language...
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What's the difference between Html.RenderPartial() and Html.Partial()? Html.RenderPartial() is an HTML helper method that was introduced in MVC1 and writes directly into the response object. Html.Partial() is an HTML helper method that was introduced in MVC2 and like the other HTML helper methods returns...
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The WebViewPage in an abstract class that inherits from the WebViewPage<TModel> generic abstract class. Two properties of the WebViewPage<TModel> generic abstract class are: Model (dynamic) ViewData (key/value collection) Among other properties, the WebViewPage adds: ViewBag (dynamic) The...
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Switching between text and code in Razor: If you're in a code block and want to emit text you can use the <text> tag: @{ if(condition == true) { <text>this is true text</text> } else { <text>this is false text</text> } } The <text> tag will not be included in the generated...
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I've been doing some work on calendars and I needed to generate a list of full moons in a given year. This got me wondering when the next blue moon will be and how many blue moons there will be this century. The next blue moon will be on 31 August 2012 at 1:57:45pm UTC and there will be 41 blue moons...
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Although I was 99.9% certain that a Contains() on a HashSet would outperform the same on a List I needed to see it happen before I could sleep again. Here is the code that I used to test it. int iterateNum = 100000000; string longString = "this is a very very very long string that is in the list";...
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I recently wrote some code that was using Parallel.ForEach() and in the function called during the Parallel.ForEach() I nested another call to Parallel.ForEach() to process a second array. This then got me thinking. If the first array that you are processing is larger than the number of cores on the...
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This is a "pattern" that I have come up with to create a chart on-the-fly using .NET 4 and MVC. I happen to be using MVC2 but I don't believe that there are any v2 features that I'm using so this will work equally well in MVC 1.0. As you'll notice it can also easily be adapted to be used in...
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